Driving band or chain



1944. G. J. ABBbTT $365,988

DRIVING BAND 0R CHAIN Filed Feb. 19, 1942 5 Sheets-Sheet l ATTOR/VEXS Dec. 26, 1944. j

G. J ABBOTT DRIVING BAND 0R CHAIN 3 Sheets-Sheet 2 Filed Feb. 19, 1942' .47 ORW s Dec. 26, 1944. J ABBOTT 2,365,988

DRIVING BAND 0R CHAIN Filed Feb. 19, 1942 5 Sheets-Sheet :5v

Patented Dec. 26, 1944 n-Nnao "STAT-ES PATENT clerics Y -Genffrey JosephAbhott, CarshaLton,,England,-;as-

signer tovlP. I. ,V.. .Chain GearslLimiteiaLondon,

Eng'laniLa company of Great Britain Applioation Febmiary 19, 1942, 'Seriatl hlo. 1431 598 I Iln Great Britain Octtdhcrii ,.-19As1 one-423a) BIClaims.

This invention relates to :driving bands :or chains for :use in power "transmission apparatus of lthe lkind comprising ea chain carrying. a series of plates, 'sla'ts :or Ilike elements (hereinafter called .slats) adapted to move across Ebut not pull'eyrof the lkind commonly known .as ta -.v-

qnilley, that 215 .130 saylhavingzflanges so formed that the (distance 'zhetween them 'ldcnreases 'nro- "gressinely from ithe SDlltBli. circumference towards (the axis rof zrotationiwith "the grooves :01- 111e- :pressions can one flange apposite :the projectin niibs or :tee'th an :the aoppos'ite :fiange. The invention is thus applicable to transmission appasratusiof the kind described :in United. Estates of remerica apatent specification 5N0. 1 ,601,662.

:In :snch rchains as at present employed, each llinl: :of the chain :is normed with ;a transverse :slotvin which isimountedra tubular .-sheath conztaining :a pack -or group of slats, rthe ends :of which :project ,trom :the open :ends of the sheath to engage the :pulley flanges, as describedlfor example in United States .of America patent specification gNo. 11150.1;663 or ,No. 1,;814,-8'83.

simprovement on this type rof chain has "been pronosediin the present .applicants United :Stains of 1Patent No. 22253851, whereintthe chain comprises :a series 10f Jinks zprovided together and :s'lat carrierseeach connected to athe chain sthe point-where two links are lpivote'd 110 nne another and :capable of rocking about the axis of the pivot relatively -to :the

:so as t-o increase fihe length-col? thellines contact between each -slat and the pulley :fianges.

The "present invention is concerned with a chain -o'f the kind describeda'bove 'as forming :the

subject of United States -of America 'rNo.

i2,225 ;851, -and according -to the invention this chain "comprises :a series .o'iilinks pivoted -torgether, 'ae-slat carrier connected to the chain :at each-pivotal point so asto be capable of locking "about "the axis of the pivot, 'and extensions'on the links "adapted to -coo'peratewith surfaces -:on $5 gchain rpartly iinrsection,

the *sl-at QaTIiBI'S when relative wpivotal movement be'tween adjacent :links :takes place :asqthe chain 1c0mes==into1=engagenmnt with a pul1ey,in such =a manner that :the projection rorgprojections on each link :act to :c-ause ra presettin-g movement of the slat :carrier at ithe rear end of .the next following slink thy :tilting this eslat carrier towards .or into the :positionureguired to enable the slats "in 'that carrier to (engage correctly the staggered depressions in the pulley flanges by which the slats :are (caused ato :niove transversely and to :ff'orm a .composite :tooth 10f the right size as ithey come into engagement therewith.

Thus fin' cha'ins of ithe .=kiml forming :thensubject or United States nf America vPatent No. 52225585 1, 558 leach slat lnarrier leaves a pulley it is :tilted 'zforwards :relatively :to the chain whereas when tit :comes into engagement with a pulley it requires 'ito she :tilted backwards in order -=that :the slats shall [engage the radial grooves -in thezpulleyidirectly. :Some degree of backward tilting :may the imparted to the .slat

carriers :as they :approach 'a pulley by arranging 'themzso that :as reach- :slat carrier is tilted back- :Wards zit hears :against :the slat carrier :behind it :so :as 'to :cause :arcorresponding movement but in a less :degree 'to such :slat carrier, and this feature may be :present fin a chain according to the invention. .In this :case the initial backward tilting of each slat'carrier'will be :caused by the backward tilting inf the ,-;carrier ;in front of it, while the ifina'l -presetting :movement will be caused by "the extension :or extensions on the links.

*With the vinvention :it will the seen that it is possible, 'by iforming the ends :of the extensions on the :linksrand' the :suriaces on ;the slat carriers which cooperate with zsuch extensions correctly, to cause substantially accurate ,presetting of the slat :carriers whereby :sudden backward :moyement vof ithe {slat marriers as they come into ten- ,gagem.en t with ra pulley; ;resulting;in :wear of :the slats, noise rpossibly zinaccurate positioning ro'f'the :sl-at roarriers acausing wear :of the slats, :is (avoided.

chamusaccordingmo ztheiinvention also. has all :the vadvantages of 29. chain yofthe kind forming athe ssubi'ect :o'f United States :of America Patent i'NQ. .:2;225,-8.51 xnientionedzin the specification of that :patent.

One iform -'.of chain anonstrncted :in acoordame with .Iinvehtion :is shown iby RWEW :ofexample in the accompanying drawings, in which 21. is a side relaxation of -:a tnortion of Figure 2 is a cross-section on the line II--II of Figure 1,

Figure 3 shows somewhat diagrammatically on a smaller scale the chain and the pulleys it engages,

Figure 4 shows a portion of the chain in perspective, parts of one slat carrier being omitted,

Figures 5, 6 and '7 show respectively before assembly a slat, a link and one end member of a slat carrier,

Figure 8.15 a. perspective view of the cover member of the slat carrier,

Figure 9 shows the locking plate therefor, and

Fig. 10 is a plan view of a section of the chain disclosing the relationship of certain operating parts with the grooved pulleys.

The chain illustrated is composed of'a number of links each of which comprises aplurality of plates A which, in the transverse direction, alternate with the similar plates of the adjacent links to which the first link is coupled by pivot pins B. The chain supports a number of carriers for the slats D which include framelike and preferably U-shaped end plates C mounted to turn on the ends of the pivots B by which successivelinks are connected to one another. Thus, the entire slat carrier, including its end plates C, can rock about the axis of the pivots B relatively to the links connected by the pivots.

The slat carriers are so formed that if it is assumed that the chain is straight, the centre parts of the slats D which are relatively shallow lie to the outer side of the, plane which contains the axis of the pivots B. The ends D- of the slats however which are of greater depth than the centres D extend inwards beyond the ends of the pivots B to a point on the inside of the plane which contains the axis of these pivots. This'is clearly shown in Figures 1 and 2 each set of slats has a back-up member D at each end.

The end plates C of the carriers, as clearly shown in Figure 7, have a flat central portion C which forms a bearing for the under sides of the slats D, and the arms of the plates C are shaped to engage slots E formed near the ends of a cover plate E which engages the tops of the slats. This cover plate is held in place by means of a locking plate F, which is of E shape form'as shown in Figure 9 and provided with a central tongue F which is bent down, as shown in Figures 1 and 4, to engage a central slot E in the cover plate after the plate E and the slats D have been assembled within the end plates C. The U-shaped plates are provided with shoulders C which are engaged by tongues E bent up from the cover plates E so as to prevent the retaining plate from being pressed into such close contact with the upper edges of the slats D as to prevent their free lateral movement across the chain.

As best shown in Fig. 10, the opposite flanges of the pulley are provided with radial grooves H, separated by projecting ribs J which have inclined edgesJ The grooves on one flange are in staggered relation to those on the other flange, i. e., the grooves H on the one flange are opposite to the ribs J on the other, and the ends of the slats D engage a groove on one flange and a rib on the other. As the chain enters the V-shaped gap between the flanges, the inclinededges J of the ribs engage the slats D and cause them to slide laterally to fill the groove H at whatever radiusthe chain is working; a

-The central edges of each cover plate. which lies between the two pairs of end plates C are bent downwards to form cam surfaces G which cooperate with the links in the following manner.

The plates A which constitute each link extend beyond the pivots B by which the links are connected together and are provided at their ends with hook-like portions A forming cams to cooperate with the cam surfaces G above referred to, and this cooperation takes place as the chain comes on to a pulley. The arrangement is .diagrammatically illustrated in Figure 3 where the chain is shown as leaving the pulley X and entering the pulley Y, the pulleys being assumed to rotate in a clockwise direction.

As the chain leaves the pulley X, each slat carrier, which was radial to the centre of the pulley when in engagement with the grooves therein, is thrown forward into the position shown by the lines 2-2 in Figure 3. As each slat carrier approaches the other pulley Y, it is first turned into the more upright position shown by the lines 3 and 4 in Figure 3 owing to the interengagement between the U-shaped slat carriers C of those slats which are about to enter the pulley Y. Before however the slats can actually engage the grooves in the pulley, the carrier is further tilted backwards so as to assume a position truly radial to the centre of the pulley Y. This is obtainedby the hook-like extension A immediately in advance of the carrier engaging the cam surface G as clearly shown by the line 5 in Figure 3. Thus each slat carrier as or just before it comes into the position shown by the line 5 in Figure 3, is rocked backwards into or approximately into the proper radial position so that when the slats enter the pulley they lie radially with respect to the centre about which the pulley rotates.

In addition, the slat carriers by virtue of the contour of the end plates C and the way in which these plates are spaced, receive a preliminary backward rocking movement, already described with reference to positions shown by the lines 3 and 4, before the final presetting operation is performed by the interengagement of the hookshaped link extensions A and cam surfaces G.

The plates of each link A are arranged in pairs, so that one plate of each pair extends beyond one of the pivots connected by the link and thus constitute a cam acting on one adjacent slat carrier whilst the other plate of each pair extends beyond the other pivot to serve as a cam acting on the other adjacent slat carrier. Thus the presetting action is obtained irrespective of the direction in which the chain travels or the pulleys rotate.

What I claim as my invention and desire to secure by Letters Patent is:

1. A transmission chain of the kind referred to for use with a V-pulley having staggered depressions in its opposite flanges comprising a series of links, pivots connecting said links together, a slat carrier mounted on said chain at each pivotal point was to be capable of, rocking about the axis of the pivot, a plurality of slats in each carrier adapted to move across but not along the chain so that the ends of at least two slats in each carrier may form a composite tooth to engage depressions in the pulley flanges,

and extensions on the links adapted to cooperate with surfaces on the slat carriers when relative pivotal movement between adjacent links takes place as the chain comes into engagement with a pulley in such manner that the link extension acts to cause a presetting movement of the slat carrier at the rear end of the next following link by tilting that carrier into the required position to enable the slats therein to engage correctly the depressions in the pulley flanges.

2. A transmission chain of the kind referred to for use with a V-pulley having staggered depressions in its oppositeflanges comprising a series of links, pivots connecting said links together, a slat carrier mounted on said chain at each pivotal point so as to be capable of rocking about the axis of the pivot, each slat carrier comprising frame-like end members having an open top, a plurality of slats which can be introduced into the carrier through said open top, and a cover adapted to retain the slats within the end frames,

said slats being adapted to move across but not along the chain so that the ends of any two slat in each carrier may form a composite tooth to engage depressions in the pulley flanges, and extensions on the links adapted to cooperate with surfaces on the slat carriers when relative pivotal movement between adjacent links takes place as the chain comes into engagement with a pulley in such manner that the link extension acts to cause a presetting movement of the slat carrier at the rear end of the next following link by tilting that carrier into the required position to enable the slats therein to engage correctly the depressions in the pulley flanges.

3. A transmission chain as claimed in claim 2 in which the cover members of the slat carriers are provided with cam surfaces adapted to cooperate with the extensions on the links.

- 4. A transmission chain as claimed in claim 2 in which the end frames ofthe carriers are of approximately U-shape and so contoured that adjacent end frames make contact with one another as the links of the chain turn about their pivots to bring about an initial tilting ofeach carrier before it is finally set by the cooperation between the link extensions and the surfaces on the carriers.

5. A transmission chain as claimed in claim 1 in which the slats have relatively shallow centre portions and ends of considerably greater depth so that these ends extend beyond the plane which contains the axis of the carrier pivots.

6. A transmission chain as claimed in claim 2 in which the slat carriers comprise approximately U-shaped end plates having a central portion to support the under sides of the slats, shoulders on the arms of the U-plates, a cover plate having stops to engage said shoulders, and a locking plate by which the slats and cover are retained in position within the carrier.

'7. A transmission chain as claimed in claim 1 in'which each link extension comprises a hooklike projection adapted to cooperate with the slat carrier at the rear of the next following link so as to tilt that slat carrier into the correct position to enable the slats within it to engage the depressions in the pulley flanges.

8. A transmission chain as claimed in claim 1 in which each link comprises a plurality of similar link-elements each having an extension at one end to engage and effect the presetting of with the result that said extensions cooperate with surfaces on the appropriate slat carrier to preset the slats it carries when the chain moves either in a clockwise or reverse direction.

GEOFFREY JOSEPH ABBOTT. 

